Because of my ongoing issues with the 1DX2 AF and AFMA Canon has requested I send RAW files for them to analyze. This is a little more detailed/specific than what they have on-line as a guide so I thought some CR folk might like to see it.
If you want to troubleshoot the AF issue, I will suggest to get a few shots with no MA, on one shot MODE with and without the extender.
Here is an example of a focus test that you can follow, if you want.
BASIC SLR FOCUS TEST
In order to isolate the issue that you are experiencing, we suggest performing the following focusing test and responding with the results. Due to the large number of factors that can affect focus, it is imperative that all of the settings below be adhered to in order to properly assess the situation.
1. If you use filters with your lenses please remove them for this test.
2. Use the ?Clear all camera settings? and ?Clear all Custom Functions? of the camera to reset the camera to its default factory settings.
3. If your camera offers the AF microadjustment feature, please ensure that it is disabled for the purposes of this test.
4. Set the Image Quality setting to "Large JPEG" (or preferably RAW if possible)
5. Set the "Picture Style" to "Standard".
6. Set the shooting mode to "aperture priority <Av>" and set the aperture to the maximum value possible (smallest f/stop) however please also ensure that it is not set any lower than f/2.8
7. Set the "ISO" speed to "100".
8. Set the "AF mode" to "One Shot". For this test, do NOT use "AI Servo" or "AI Focus" modes.
9. Set the "Drive Mode" to "Single Shot". For this test, do NOT use "Continuous" shooting mode.
10. Select only the centre auto-focus point.
11. If you use a tripod, please disable the Image Stabilization of the lens by moving the "Stabilizer" switch on the lens to the "OFF" position.
12. Place three objects of the same size on a table at different distances from the camera. From left to right, place the left most object closest to the camera and the right most object furthest from the camera. From front to back, space the objects out by about 2 to 3 inches. For easier analysis, we recommend using objects that contain text or writing on them and that contain a fair amount of contrast (i.e. avoid using objects that are completely one colour).
13. Compose or frame the image in the viewfinder so that the three objects occupy and fill as much of the frame as possible. Also, please ensure that the iamge is taken at eye level and not an an angle.
14. Use the centre auto-focus point to achieve focus on the centre object and then, without re-framing, capture the image. Please ensure that the centre AF point is aimed towards a part of the object that contains contrast (i.e. avoid having the AF point land on a part of the object that is completely one colour).
15. Please ensure that there is more than adequate lighting in the room. If possible this test should be performed outdoors in full daylight.
16. Please ensure that the lens is "de-focused" or purposely thrown out of focus in between every test shot. To do this, focus on an object that is located at a different distance to your intended subject and then re-perform the test.
17. Optional: redo steps 1-16 using the "Live View Shooting" feature of your camera (if available on your model). This will help isolate the issue even further.
Note that, after downloading images to your computer from a digital camera, it is tempting to magnify or print out just a part of the image once downloaded to your computer. This can magnify small errors in AF that would otherwise not be apparent when being viewed at a more traditional print size. As a result, you may see slight errors in AF magnified many times over that would not normally be visible when the image is printed. Even if small errors in AF are visible on the computer monitor, these errors may not be visible when the image is viewed as a full size print.
Please reply to this message with the image(s) captured during this test attached. Please ensure that the images are sent using the file attachment feature of your particular email system. Images are not to be embedded or pasted into the email. In the case that the file size of the images is too large for email, you may also send your files via any file sharing web site of your choosing (i.e. www.wikisend.com
, Dropbox etc.) and provide us with the web link. In addition, please e-mail images that have not been edited (i.e. no adjustments, no cropping, no resizing) and have been saved in the camera's native JPG/JPEG file format or RAW file format (if available).
Upon receipt of the image(s) we will examine them and will then contact you with our findings and recommendations.